Refactor: Improve config, storage, and UI components

Commit notes

This commit includes several refactors and improvements across the backend and frontend. Key changes include:

- **Backend:** - Added validation for `DATABASE_URL` environment variable in `drizzle.config.ts`, `mark-migrations-applied.ts`, and `db/index.ts`. - Improved storage configuration handling in `config/index.ts` for MinIO and R2, adding explicit checks for required credentials. - Minor code style and logging improvements in `events.ts`, `audio-analysis.ts`, `library-events.ts`, `worker.ts`, and `sample-packs.ts`. - Reordered imports in `workspace-setup.ts`.

- **Frontend:** - Refactored Command Palette and Header components for better UI/UX and accessibility. - Improved ProjectList and WorkspaceContextIndicator components for clarity and functionality. - Updated PackOrganizer to use SvelteSet correctly for sample selection. - Refactored WorkspaceProjectNav with clearer state management and improved drawer handling. - Made minor UI adjustments in various components for consistency. - Removed unused imports and code in several frontend files.

Co-authored-by: armin.naimi <[email redacted]>